A common side effect of excessive protein consumption is digestive issues, which may include bloating, gas, and constipation. Consuming high amounts of protein can lead to increased intake of fat and other nutrients, which might disrupt the balance of the diet. Moreover, over-reliance on protein can strain the kidneys, especially in individuals with pre-existing kidney conditions, as they are responsible for filtering out the byproducts of protein metabolism. Moderation is key to maintaining a balanced nutrient intake.